Side rail: 13" rectangular, long
ThePF40 side rail is the long version of the super structure to fit on the long frame.
The PF 40 is made of tubular aluminum 3/4" in diameter with a .058 wall thickness. It is 64 incheds long and formed to a rectangle 13inches high and 39.25 inches on center.
The PF 40 fits onto the long Equinox trailer frame.